Geochronology of the Tananao Schist complex, Taiwan, and its regional tectonic significance
Journal
Tectonophysics
Journal Volume
125
Journal Issue
1-3
Pages
103-124
Date Issued
1986
Author(s)
Abstract
Isotopic analyses (Rb-Sr, U-Pb, Sm-Nd, K-Ar) on rocks and minerals of the Tananao Schist complex (the Tailuko-Tienhsiang and the Nanao areas of eastern Taiwan) have yielded significant new age data corresponding to several important geologic events in the crustal evolution of Taiwan. The ages and corresponding events are summarized as follows: Crustal history 0-10 Ma: Arc-continent collision; regional metamorphism III (Penglai Orogeny). 35-40 Ma: Continental rifting and opening of the South China Sea; regional metamorphism II. 80-90 Ma: Granitic intrusions in Taiwan; regional metamorphism I (Nanao Orogeny). Overlapped with the most important world-wide, particularly circum-Pacific, thermal events of 90-110 Ma (Jahn, 1974; Jahn et al., 1976). 200-240 Ma: Deposition of carbonates and clastic sediments, probably in a geosynclinal environment. Beginning of the crustal history of Taiwan. Pre-crustal history 500-650 Ma (or older): Separation of protoliths for the granitoids of Taiwan from a chondritic (or depleted mantle) reservoir. 1000-1700 Ma: Crystallization of zircons, of which some grains have survived and been finally incorporated in the young (ca. 90 Ma) granitic magmas. © 1986.
SDGs
Type
journal article